## College Physics (4th Edition)

(a) Students should plot $v$ on the vertical axis and $r^2$ on the horizontal axis. (b) $n = \frac{2~g(\rho-\rho_f)}{(9)(slope)}$
$v = \frac{2r^2~g(\rho-\rho_f)}{9n}$ (a) To test this relationship. students should plot $v$ on the vertical axis and $r^2$ on the horizontal axis. (b) When we plot $v$ on the vertical axis and $r^2$ on the horizontal axis, the slope of the line will be $\frac{2~g(\rho-\rho_f)}{9n}$ We can find an expression for $n$: $slope = \frac{2~g(\rho-\rho_f)}{9n}$ $n = \frac{2~g(\rho-\rho_f)}{(9)(slope)}$